just to let you know, I keep getting 500 server errors on your blog: http://screencast.com/t/XCB408gcx1Z so I commented here instead of on your blog.
On a blog (with multisite enabled) that runs your plugin version 4.0 I jsut saw the following stats:
Stop Spammers has stopped 15521 spammers since 2012/11/09.
Cached Bad IP 15171
This smelled weird, as that is way more spam than I ever got so I checked the history and for whatever reason my own server's IP was blacklisted?
date/time email IP author, user/pwd script reason blog
2012/12/11 16:35:58 -- 184.108.40.206 -- /wp-cron.php?doing_wp_cron=1355236558.1089560985565185546875 Cached bad ip
I have cleared the cache and added the server's IP to the white list. Any idea why it would block my "wp cron" job?